of a material. Diastase and protease are the most important enzymes found in flour. Diastase converts starch to sugar, and the yeast acts upon the sugar to produce  carbon  dioxide  and  other  fermentation products. Protease softens the gluten and, when this enzyme is lacking, the dough will not have the desired elasticity. Fat.—  Wheat   flour   contains   approximately 1.5-percent fat. The major portion of the fat of wheat grain  is  removed  during  the  milling  process.  Although the fat content of flour is very low, this is what causes flour to become rancid if flour is stored for long periods under warm and humid conditions. WATER.—  In many bakery products, including bread, the amount of water used is second only to the amount of flour. Water contains minerals. The amount and kind of minerals contained in the water vary from one part of the country to another. These variations affect the properties of the dough and the finished bread. Water is necessary to form gluten from the protein of flour, thereby giving the dough its elasticity and its gas retaining property. Gluten absorbs twice its own weight of water. The amount of water used determines the consistency and the temperature of the dough after it is mixed. Water dissolves the salt and the sugar, makes it possible for the enzymes to act, and holds the yeast in suspension until it is added to the other ingredients and the  fermentation  begins. SALT.—  Very little salt is used in making bread, but the amount used is essential, for it performs a very important  function.  Without  salt,  fermentation  in  dough is too rapid, and the baked product becomes too coarse. With too much salt, the fermentation process is slowed, and  the  bread  becomes  soggy.  Salt  strengthens  gluten and helps it to expand, improves the color of baked products,  and  enhances  the  flavor. SUGAR.— During fermentation, part of the sugar is converted into a form that can be used as food for the yeast. Starches are converted into sugar that produces carbon dioxide gas and alcohol and that causes the dough to expand, making it softer and more flexible. This sugar in the bread contributes to the color of the crust, the taste of the baked loaf, the toasting qualities of  the  bread,  the  texture,  the  moisture  retaining  qualities, and the nutritional value. Sugar is also a tenderizer. All  sugars  do  not  have  the  same  degree  of sweetness,  since  sweetness process  through  which  the sugar, for example, is less depends  upon  the  refining sugar has passed. Brown highly  refined  than  white sugar and, therefore, is not so sweet. Brown sugar lends a pleasant taste to cooked or baked products, and syrups can be used as a substitute for regular sugar. Corn syrup, honey,  or  molasses  improves  the  flavor  of  cookies  and helps retain their moisture. SHORTENING.—  Shortening is the animal or vegetable fat that is used in baking. There are two general  types  of  shortening-solid  and  liquid.  The solid-type shortening is recommended for use in bread dough because it can be more thoroughly distributed through the dough. The reason for this is that it will not saturate the flour it touches. Although the liquid-type shortening can be used effectively, the dough must be well formed before the oil is added. The liquid-type shortening is mainly used in recipes that call for melted shortening, such as some cake and bread recipes. Shortening compounds are composed of deodorized animal  and  vegetable  fats  mechanically  blended  to  give a final product of acceptable elasticity and satisfactory baking quality. There are two types of solid shortening compounds used in the Navy GM—general-purpose shortening  and  bakery  shortening  (emulsifier-type). General-Purpose Shortening.— General-purpose shortening is a high-grade shortening that has excellent baking qualities. General-purpose  shortening  should not  be  substituted  in  recipes  that  specify  bakery-type shortening. Bakery  Shortening.—  Bakery  shortening  or emulsifier-type  shortening  is  hydrogenated  shortening to which an emulsifying agent has been added. This gives  the  shortening  exceptional  ability  to  blend  with other  ingredients. SALAD OILS.— Salad  oils  are  generally  used  in the preparation of salad dressing and in recipes that specify  oil. Oil  should  not  be  substituted  for general-purpose  or  emulsifier-type  shortening  in  recipes specifying those types. BUTTER.—  Butter is the fatty constituent of milk that  is  separated  from  the  other  milk  constituents  by churning. Butter is used most often as a spread, but it has many other uses in food preparation. When butter is  substituted  for  other  shortening,  you  should  adjust your  recipe.  Butter  contains  salt,  milk,  and  moisture  so the  salt,  milk,  and  liquid  in  the  recipe  should  be decreased accordingly. The fat content of butter is less than that of other shortening; therefore, more butter should be used in the recipe. MILK.— Milk is almost a complete food. Nonfat dry milk contains all the food qualities of whole milk 8-2